WO2012127404A2 - Ergonomic handle for haptic devices - Google Patents

Ergonomic handle for haptic devices Download PDF

Info

Publication number
WO2012127404A2
WO2012127404A2 PCT/IB2012/051303 IB2012051303W WO2012127404A2 WO 2012127404 A2 WO2012127404 A2 WO 2012127404A2 IB 2012051303 W IB2012051303 W IB 2012051303W WO 2012127404 A2 WO2012127404 A2 WO 2012127404A2
Authority
WO
WIPO (PCT)
Prior art keywords
handle
user
hand
dof
orientation
Prior art date
Application number
PCT/IB2012/051303
Other languages
French (fr)
Other versions
WO2012127404A3 (en
Inventor
Laura SANTOS CARRERAS
Ricardo Beira
Hannes Bleuler
Original Assignee
Ecole Polytechnique Federale De Lausanne (Epfl)
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ecole Polytechnique Federale De Lausanne (Epfl) filed Critical Ecole Polytechnique Federale De Lausanne (Epfl)
Publication of WO2012127404A2 publication Critical patent/WO2012127404A2/en
Publication of WO2012127404A3 publication Critical patent/WO2012127404A3/en

Links

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05GCONTROL DEVICES OR SYSTEMS INSOFAR AS CHARACTERISED BY MECHANICAL FEATURES ONLY
    • G05G9/00Manually-actuated control mechanisms provided with one single controlling member co-operating with two or more controlled members, e.g. selectively, simultaneously
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70Manipulators specially adapted for use in surgery
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70Manipulators specially adapted for use in surgery
    • A61B34/74Manipulators with manual electric input means
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70Manipulators specially adapted for use in surgery
    • A61B34/76Manipulators having means for providing feel, e.g. force or tactile feedback
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B2017/0042Surgical instruments, devices or methods, e.g. tourniquets with special provisions for gripping
    • A61B2017/00424Surgical instruments, devices or methods, e.g. tourniquets with special provisions for gripping ergonomic, e.g. fitting in fist

Definitions

  • the present invention generally relates to the haptic devices field, and more specifically to an ergonomically optimized spherical wrist with at least gripping force feedback capabilities.
  • the present invention concerns an ergonomic handle with a remote center of rotation and providing hand orientation and force feedback.
  • a haptic device is an input/output interface that can interact with the user by sensing users movement (input) and generating a force (output) in response to this movement.
  • the input and output information can be inverted if the device is impedance controlled (force/motion) or admittance controlled (motion/force).
  • haptic devices are increasingly been applied in teleoperation tasks in which haptic information can enhance user's performance and increase safety.
  • the teleoperated robots can work in hazardous environments, perform distant surgical procedures, or work with objects in a totally different scale.
  • a haptic device allows scaling the forces and the motion to perform bigger forces or more precise movements without loosing the haptic information involved in the manipulation.
  • Haptic device components are very similar to the ones of an industrial robot: actuators, transmissions and sensors, attached to a task specific mechanical structure.
  • the dynamic physical interaction with a human operator imposes supplementary constraints with respect to other standard mechatronic devices.
  • the motion and the force generated by the haptic interface should be free of parasite effects and thus the designed mechanisms should minimize inertia, friction, and backlash, and maximize stiffness, workspace and bandwidth. Since haptic devices will have to control the interaction force with the user, safety features and ergonomics are crucial factors.
  • a further aim of the present invention is to propose a handle that can be used in tasks requiring high dexterity and precision such as teleoperated surgery or virtual simulators for training or games.
  • An idea of the present invention is to provide an ergonomic handle for a haptic interface that acquires the orientation of the user's hand and provides force feedback in the gripping action and features safety brakes for the orientations.
  • a DC motor is used to simulate the gripping force when gripping virtual or distal objects.
  • Pneumatic brakes are preferably used to block the orientation of the user's hand if any problem occurs.
  • other equivalent means are possible as well.
  • an ergonomic grasping mechanism with force feedback has been designed to distribute the force among all the fingers and combining both precision grip and a power grip finger postures see reference [5]. This design allows the operator to perform fine manipulation while maintaining the appropriate hand stiffness and force control.
  • the present invention concerns therefore an ergonomic handle comprising:
  • the handle comprises a grasping mechanism with an input sensor to measure the user's hand aperture.
  • the handle involves all fingers to grasp the device and the thumb to control the action.
  • the moving part of the grasping mechanism has the axis ergonomically located to follow the natural thumb movement.
  • the fixed part of the grasping mechanism has a curved shape to avoid finger tension.
  • the moving part is actuated to provide grasping feedback.
  • the handle further comprises brakes to block user's hand orientation.
  • the handle further comprises actuators to provide torque feedback.
  • the handle further comprises a contact sensor, to detect the presence of the user's hand.
  • the handle further comprises a safety feature that blocks user's hand movement when the user removes the hand from the handle.
  • the handle further comprises a safety feature that blocks user's hand movement when a safety issue arouses.
  • the double parallelogram is separated in two parallel link chains to increase the stiffness of the mechanism.
  • the handle further comprises split axis to increase the workspace of the mechanism.
  • the handle is assembled on another input device providing extra DOF.
  • the handle further comprises Peltier elements to provide temperature tactile sensations.
  • the handle further comprises actuators providing vibrations to recreate tactile sensations on the user's hand skin.
  • the handle further comprises a tactile display composed by an array of pins to display a tactile pattern by indenting the skin of fingertip.
  • the array of pins is actuated in a pulsated manner to simulate heartbeats.
  • a device such as a haptic device, comprises a handle as defined herein.
  • Figure 1 illustrates a preferred embodiment with a hand model
  • Figure 2 illustrates simple and double parallelogram mechanisms
  • Figure 3 illustrates extreme positions of the spherical for the roll DOF
  • Figure 4 illustrates extreme positions of the spherical for the yaw DOF
  • Figure 5 illustrates extreme positions of the spherical for the pitch DOF
  • Figure 6 illustrates a detailed view of the grasping feedback system
  • Figure 7 illustrates a grasping DOF;
  • Figure 8 illustrates a detailed view of the cable transmission
  • Figure 9 illustrates tactile cues
  • FIG. 10 illustrates a detailed view of the pneumatic transmission system.
  • Figure 1 illustrates an illustrative embodiment with a hand model.
  • the proposed spherical mechanism 1 has been economically designed so that the user will mainly control the device with postures that slightly differ from the neutral position of the wrist.
  • the spherical mechanism 1 is based on a double parallelogram structure 11 with a remote center of rotation 12.
  • Fully decoupled 2-DOF or 3-DOF spherical mechanisms 1 can be synthesized based on elementary motion generators.
  • a parallelogram 10 (Figure 2(a)) can be used to displace the pointing motion in parallel to the actuated link.
  • Each point of the bottom link of the pantograph 10 performs a circular displacement, however the link remains aligned parallel to the top link.
  • the rotation is thus created by a 2-DOF linear displacement around a fixed point.
  • the relative displacement between two platforms parallel 11 to each other ( Figure 2(b)) can be used as well for circular motion generation. In this case a virtual pivot point or remote-center of rotation 12 is obtained, as the rotation is performed around a point, which is not part of the linkage 11.
  • the remote center of rotation 12 is located at the center of the user's hand 13 to provide a natural control of the orientation of the hand 13.
  • This mechanism provides three degrees of freedom of orientation, roll, pitch and yaw that coincide with the pronosupination (Figure 3], extension- flexion ( Figure 4) and ulnar-radial deviation (Figure 5) degrees of freedom (DOF) of the human wrist respectively.
  • the mechanism has been designed to provide the corresponding stroke to each degree of freedom.
  • the stroke of the pitch DOF which corresponds to the ulnar-radial deviation of the wrist ( Figure 5] is limited to avoid postures that can lead to tenosynovitis, carpal tunnel syndrome or wrist physical discomfort.
  • the profiles of the adjacent links make contact at the limit of the stroke.
  • the order of the first and the third DOF can be interchanged.
  • each pivot joint features two preloaded bearings.
  • the double parallelogram is then doubled in two forming two parallel link chains.
  • the axes are as well split in two parts and each of them features a bearing.
  • This provides free space between the two double parallelograms 11 to allow hand movement especially for the yaw DOF ( Figure 4).
  • Each DOF features a magnetic encoder 2, 4, 6 to measure the angles and thus determine the orientation of the user's hand by solving the handle kinematics.
  • the device could alternatively use optical encoders 2, 4, 6 or potentiometers 2, 4, 6 to measure the angle of each DOF.
  • the cylinders 2, 4, 6 represented in the Figures 1-5 represent the location of the actuators and/or position sensors 2 and 6 for the DOFs roll and yaw.
  • the actuators and sensors 4 for the pitch DOF can be assembled to any of the pivot joints composing the double parallelogram 11, as indicated in figure 1.
  • the ergonomic handle is cinematically decoupled from the rest of the haptic device where it will be connected. This means that the user can use different hand orientations to approach the same point into the workspace. Furthermore, the user can change the hand orientation without changing the position.
  • the device can be mechanically grounded through the interface plate 3 ( Figure 1). Additionally, this device could be attached to a haptic device that provides force feedback in the translations to add four extra DOF and increase its workspace. However, the DOF of the ergonomic handle are mechanically independent of the haptic device on which it is being installed and thus move relative to them.
  • the proposed mechanism includes an actuator for each DOF to provide torque feedback in each orientation, see Figure 1.
  • the present prototype uses brakes it could also integrate a motor in each DOF to provide active torque feedback.
  • the grasping mechanism 7 is composed of two main parts (see Figure 6): 1] The moving part 21 that interacts with the user's thumb and that is actuated by a motor 22 and
  • the moving part 21 rotates around an axis attached to the fixed part of the handle.
  • the fixed part 23 of the handle is directly attached to the yaw DOF of the spherical mechanism.
  • the grasping mechanism 7 has been designed to distribute the force among all the fingers 20, 24 and to combine both precision grip and a power grip finger postures see reference [5]. This design allows the operator to perform fine manipulation while maintaining the appropriate hand stiffness and force control.
  • the shape of the fixed part 23 of the handle is curved to prevent finger 24 tendons from being stretched and tense ( Figure 6).
  • the moving part 21 is actuated through a cable 25 driven mechanism that provides force feedback when grasping a virtual or distal object.
  • the cable 25 is wrapped around the motor 27 shaft 26 in two opposite directions and it passes through the shaft 26 in the middle of its length, see Figure 8. This way of assembling the cable 25 equilibrates the forces applied to the shaft 26 preventing motor failures.
  • the rest of the cable 25 is wrapped around the motor 27 shaft 26 in both directions in order to have enough cable to turn the outer surface of the pulley 28.
  • the two extremities of the cable 25 are then fixed to the pulley 28.
  • the axis 29 of the pulley 28 is located towards the axis of the human's thumb 20. Furthermore, the motor 27 is attached to the fixed part of the gripping mechanism 7 through a slanted plane replicating the axis orientation of the human's thumb 20. This ergonomic configuration allows the user to move its thumb 20 naturally.
  • the stroke of the gripping mechanism is 90 degrees.
  • a pin located in the motor 27 fixation limits the stroke of the moving pulley 28 for safety reasons.
  • the radius of the pulley is R.
  • the motor shaft 26 extension has a radius r. With the angle measured by the encoder integrated in the motor 27, the opening angle of the user's hand can be calculated.
  • the cable 25 transmission amplifies the motor torque and the encoder resolution by a ratio of R/r.
  • All the fingers 20, 24 are attached to the gripping mechanism by adjustable straps 30, 31 or other equivalent means.
  • the lack of tactile information prevents the user to perform common haptic explorations when manipulating virtual or distal objects. For instance, in the case of teleoperated robotic surgery, surgeons cannot palpate the internal tissues to localize hidden anatomical structures. During surgical procedures, palpation is often carried out in order to determine the position of arteries. This task is regularly performed to locate needle insertion sites for regional anesthesia, or to prevent accidental rupture of arteries.
  • Temperature information can also be displayed directly to the user's fingertip thought a display integrating several Peltier elements 32, see Figure 9(b).
  • Vibration actuators such as small dc motors with an eccentric mass attached or voice coils, can also convey additional information such as the slippage of an object between the fingertips.
  • These displays can be integrated on the fixed part of the grasping system under the chosen finger.
  • the control electronics might be preferably apart to reduce the weight and size of the device.
  • the information displayed by this system might be measured by sensors integrated in the gripper of the slave robot.
  • the array of pins 33 could render the information sensed by a matrix of pressure sensors.
  • a sensor such as a Resistance Temperature Detector (RTD)
  • RTD Resistance Temperature Detector
  • thermistor included in the slave robot sense directly the temperature of the contact point with the object.
  • the device can directly simulate the thermal or tactile characteristics of the virtual object commanded by the computer.
  • the ergonomic handle features safety brakes for the orientations. They may comprise a pneumatic brake system (see Figure 10].
  • the main component of this braking system is a pneumatic hub 40 with a cylindrical air chamber 41 connected to an entrance of air. This cylindrical hub is attached to the fixed link 44 of the DOF by two antirotational pins. A moving shaft 42 passes though the hub 40 without making contact with it and is attached to an external tambour 43.
  • the air inflates the pneumatic chamber 41 of the hub 40 and thus, it makes contact with the external tambour 43. Consequently, the fix part 44 and the moving shaft 42 are mechanically connected preventing relative movement between them.
  • magnetic particle brakes or other types of friction brakes can be used to generate a passive resistance or friction in each DOF.
  • all or some of the actuator and sensor pairs can include only sensors to provide an apparatus without torque or grasping force feedback along designated DOF.
  • the presence sensor should be able to detect if the handle is being touched, even if the user is wearing rubber gloves or if the hand presents high level of humidity. Additionally, the presence sensor should only detect the user's hand when it is actually in contact with the ergonomic handle and not when it is just near. In this embodiment, the most suitable sensor was found to be a capacitive sensor. Nevertheless, a pressure sensor could be also be used and achieve the same result. Of course, other equivalent means and sensors may be used.
  • the device of the present application can be used in many different fields and adapted for said fields (materials, sizes etc): medical applications, simulation applications, game applications, etc. REFERENCES (all incorporated by reference in their entirety in the present application)

Abstract

A ergonomic handle that can be added to existing haptic devices, composed by a spherical mechanism providing hand orientation and a grasping mechanism is shown. Both the proposed spherical mechanism and the handle have been ergonomically designed to avoid postures that could lead to physical discomfort or cumulative traumas such as carpal tunnel syndrome or tenosynovitis.

Description

ERGONOMIC HANDLE FOR HAPTIC DEVICES
CORRESPONDING APPLICATION
The present application claims the priority of US application N° 61/453,972 the content of which is incorporated in its entirety in the present application.
FIELD OF INVENTION
The present invention generally relates to the haptic devices field, and more specifically to an ergonomically optimized spherical wrist with at least gripping force feedback capabilities.
More specifically, the present invention concerns an ergonomic handle with a remote center of rotation and providing hand orientation and force feedback.
BACKGROUND OF THE INVENTION
A haptic device is an input/output interface that can interact with the user by sensing users movement (input) and generating a force (output) in response to this movement. The input and output information can be inverted if the device is impedance controlled (force/motion) or admittance controlled (motion/force).
These devices are increasingly been applied in teleoperation tasks in which haptic information can enhance user's performance and increase safety. The teleoperated robots can work in hazardous environments, perform distant surgical procedures, or work with objects in a totally different scale. In those applications a haptic device allows scaling the forces and the motion to perform bigger forces or more precise movements without loosing the haptic information involved in the manipulation. Haptic device components are very similar to the ones of an industrial robot: actuators, transmissions and sensors, attached to a task specific mechanical structure. However, the dynamic physical interaction with a human operator imposes supplementary constraints with respect to other standard mechatronic devices. For instance, the motion and the force generated by the haptic interface should be free of parasite effects and thus the designed mechanisms should minimize inertia, friction, and backlash, and maximize stiffness, workspace and bandwidth. Since haptic devices will have to control the interaction force with the user, safety features and ergonomics are crucial factors.
Regarding the ergonomics specifications of this kind of devices, it has been proved (see references [7] [2] [10]) that forces applied by the fingers while grasping an object are highly related with wrist position, thus one of the specifications is to keep the user's wrist always close to the neutral position. In addition, fatigue must be taken into account during the device design since it might prevent the user to maintain the required force. The task duration represents an important risk factor as it plays a significant role in the development and onset of musculoskeletal injuries; longer tasks duration will definitely increase the risk of adverse effects produced by a poor ergonomic design. For instance, in a teleoperated surgical system, this is a safety rule that concerns both patient and surgeon, since this could lead to a lower performance during the procedure and thus, a worse result for the patient.
Even though robotic teleoperated systems have overcome many ergonomic drawbacks in tasks where the user had to work in uncomfortable postures such as minimal invasive surgical procedures or micromanipulation, there is still room for improvement. Recent studies showed that commercially available teleoperated surgical robots still present some sources of discomfort, specifically neck and back muscle hardening due to the long-last non-neutral back position (see references [3] [4]) and tension on the fingers. The aforementioned reasons motivated the design of an ergonomically optimized user interface decreasing user's mental stress and the likeliness of work-related physical injuries. BRIEF SUMARY OF INVENTION
It is an aim of the present invention to improve the known devices and methods. More specifically, it is an aim of the present invention to provide an ergonomically optimized handle for the use of haptic interfaces.
Additionally, it is an aim of the present invention to propose an ergonomic handle for haptic interfaces being used in teleoperation tasks or to interact with virtual reality.
A further aim of the present invention is to propose a handle that can be used in tasks requiring high dexterity and precision such as teleoperated surgery or virtual simulators for training or games.
Features of the device according to the present invention are defined in the appended independent claims.
Dependent claims define specific embodiments of the present invention.
An idea of the present invention is to provide an ergonomic handle for a haptic interface that acquires the orientation of the user's hand and provides force feedback in the gripping action and features safety brakes for the orientations.
Preferably, a DC motor is used to simulate the gripping force when gripping virtual or distal objects. Pneumatic brakes are preferably used to block the orientation of the user's hand if any problem occurs. Of course, other equivalent means are possible as well.
In addition, an ergonomic grasping mechanism with force feedback has been designed to distribute the force among all the fingers and combining both precision grip and a power grip finger postures see reference [5]. This design allows the operator to perform fine manipulation while maintaining the appropriate hand stiffness and force control.
The present invention concerns therefore an ergonomic handle comprising:
- a plurality of degrees of freedom of orientation in which at least one of them is accomplished by a double parallelogram;
- a remote center of rotation located inside the user's hand; - an input sensor per DOF, to measure the user's hand orientation.
In an embodiment the handle comprises a grasping mechanism with an input sensor to measure the user's hand aperture.
In an embodiment the handle involves all fingers to grasp the device and the thumb to control the action.
In an embodiment the moving part of the grasping mechanism has the axis ergonomically located to follow the natural thumb movement.
In an embodiment the fixed part of the grasping mechanism has a curved shape to avoid finger tension.
In an embodiment the moving part is actuated to provide grasping feedback.
In an embodiment the handle further comprises brakes to block user's hand orientation.
In an embodiment the handle further comprises actuators to provide torque feedback.
In an embodiment the handle further comprises a contact sensor, to detect the presence of the user's hand.
In an embodiment the handle further comprises a safety feature that blocks user's hand movement when the user removes the hand from the handle.
In an embodiment the handle further comprises a safety feature that blocks user's hand movement when a safety issue arouses. In an embodiment the double parallelogram is separated in two parallel link chains to increase the stiffness of the mechanism.
In an embodiment the handle further comprises split axis to increase the workspace of the mechanism.
In an embodiment, the handle is assembled on another input device providing extra DOF.
In an embodiment, the handle further comprises Peltier elements to provide temperature tactile sensations.
In an embodiment the handle further comprises actuators providing vibrations to recreate tactile sensations on the user's hand skin.
In an embodiment the handle further comprises a tactile display composed by an array of pins to display a tactile pattern by indenting the skin of fingertip.
In an embodiment the array of pins is actuated in a pulsated manner to simulate heartbeats.
In an embodiment a device, such as a haptic device, comprises a handle as defined herein.
BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a preferred embodiment with a hand model; Figure 2 illustrates simple and double parallelogram mechanisms; Figure 3 illustrates extreme positions of the spherical for the roll DOF; Figure 4 illustrates extreme positions of the spherical for the yaw DOF; Figure 5 illustrates extreme positions of the spherical for the pitch DOF; Figure 6 illustrates a detailed view of the grasping feedback system; Figure 7 illustrates a grasping DOF;
Figure 8 illustrates a detailed view of the cable transmission; Figure 9 illustrates tactile cues;
Figure 10 illustrates a detailed view of the pneumatic transmission system. DETAILED DESCRIPTION OF THE INVENTION
Figure 1 illustrates an illustrative embodiment with a hand model.
Spherical mechanism 1
The proposed spherical mechanism 1 has been economically designed so that the user will mainly control the device with postures that slightly differ from the neutral position of the wrist.
The spherical mechanism 1 is based on a double parallelogram structure 11 with a remote center of rotation 12.
Fully decoupled 2-DOF or 3-DOF spherical mechanisms 1 can be synthesized based on elementary motion generators. A parallelogram 10 (Figure 2(a)) can be used to displace the pointing motion in parallel to the actuated link. Each point of the bottom link of the pantograph 10 performs a circular displacement, however the link remains aligned parallel to the top link. The rotation is thus created by a 2-DOF linear displacement around a fixed point. The relative displacement between two platforms parallel 11 to each other (Figure 2(b)) can be used as well for circular motion generation. In this case a virtual pivot point or remote-center of rotation 12 is obtained, as the rotation is performed around a point, which is not part of the linkage 11. In the present embodiment the remote center of rotation 12 is located at the center of the user's hand 13 to provide a natural control of the orientation of the hand 13. This mechanism provides three degrees of freedom of orientation, roll, pitch and yaw that coincide with the pronosupination (Figure 3], extension- flexion (Figure 4) and ulnar-radial deviation (Figure 5) degrees of freedom (DOF) of the human wrist respectively. Furthermore, the mechanism has been designed to provide the corresponding stroke to each degree of freedom. For instance, the stroke of the pitch DOF, which corresponds to the ulnar-radial deviation of the wrist (Figure 5] is limited to avoid postures that can lead to tenosynovitis, carpal tunnel syndrome or wrist physical discomfort. As it can be seen in Figure 5, to constrain the movement of the double parallelogram 11 the profiles of the adjacent links make contact at the limit of the stroke.
Alternatively, in the presented embodiment the order of the first and the third DOF can be interchanged.
This type of mechanism has been already used for applications in which a tool or a manipulator should rotate around a point in which due to space constrains mechanical components cannot be placed. For instance, in the patent US7594912 robotic devices and other systems including an offset remote center parallelogram manipulator linkage constraining a position of a surgical instrument during minimally invasive robotic surgery are disclosed. In reference [9] a haptic device for the surgical training of hysteroscopy, a gynecologic intervention based in a double parallelogram linkage is also presented. However, to the author's best knowledge this is the first device that uses double parallelogram kinematics to place the remote center of rotation in the center of the user's hand to develop and ergonomic haptic handle.
To reduce backlash and friction, each pivot joint features two preloaded bearings. To increase stiffness of the overall handle the double parallelogram is then doubled in two forming two parallel link chains. The axes are as well split in two parts and each of them features a bearing. This provides free space between the two double parallelograms 11 to allow hand movement especially for the yaw DOF (Figure 4). Each DOF features a magnetic encoder 2, 4, 6 to measure the angles and thus determine the orientation of the user's hand by solving the handle kinematics. The device could alternatively use optical encoders 2, 4, 6 or potentiometers 2, 4, 6 to measure the angle of each DOF. The cylinders 2, 4, 6 represented in the Figures 1-5 represent the location of the actuators and/or position sensors 2 and 6 for the DOFs roll and yaw. The actuators and sensors 4 for the pitch DOF can be assembled to any of the pivot joints composing the double parallelogram 11, as indicated in figure 1.
The ergonomic handle is cinematically decoupled from the rest of the haptic device where it will be connected. This means that the user can use different hand orientations to approach the same point into the workspace. Furthermore, the user can change the hand orientation without changing the position.
The device can be mechanically grounded through the interface plate 3 (Figure 1). Additionally, this device could be attached to a haptic device that provides force feedback in the translations to add four extra DOF and increase its workspace. However, the DOF of the ergonomic handle are mechanically independent of the haptic device on which it is being installed and thus move relative to them.
Alternative means to attach the ergonomic handle to a haptic device are possible. For instance, instead of a plate interface 3 that has to be screwed it could be assembled through a clip mechanism or through a slider member or other equivalent means.
The proposed mechanism includes an actuator for each DOF to provide torque feedback in each orientation, see Figure 1. Although the present prototype uses brakes it could also integrate a motor in each DOF to provide active torque feedback. To provide active torque feedback DC motors, step motors or AC motors could be used. Nevertheless, these actuators should be backlash and friction free and preferably back drivable to preserve the transparency of the overall device.
Grasping feedback system 7
The grasping mechanism 7 is composed of two main parts (see Figure 6): 1] The moving part 21 that interacts with the user's thumb and that is actuated by a motor 22 and
2] the fixed part 23 that is grasped with the rest of the fingers 24.
The moving part 21 rotates around an axis attached to the fixed part of the handle. The fixed part 23 of the handle is directly attached to the yaw DOF of the spherical mechanism.
The grasping mechanism 7 has been designed to distribute the force among all the fingers 20, 24 and to combine both precision grip and a power grip finger postures see reference [5]. This design allows the operator to perform fine manipulation while maintaining the appropriate hand stiffness and force control.
The shape of the fixed part 23 of the handle is curved to prevent finger 24 tendons from being stretched and tense (Figure 6).
The moving part 21 is actuated through a cable 25 driven mechanism that provides force feedback when grasping a virtual or distal object. The cable 25 is wrapped around the motor 27 shaft 26 in two opposite directions and it passes through the shaft 26 in the middle of its length, see Figure 8. This way of assembling the cable 25 equilibrates the forces applied to the shaft 26 preventing motor failures. The rest of the cable 25 is wrapped around the motor 27 shaft 26 in both directions in order to have enough cable to turn the outer surface of the pulley 28. The two extremities of the cable 25 are then fixed to the pulley 28.
The axis 29 of the pulley 28 is located towards the axis of the human's thumb 20. Furthermore, the motor 27 is attached to the fixed part of the gripping mechanism 7 through a slanted plane replicating the axis orientation of the human's thumb 20. This ergonomic configuration allows the user to move its thumb 20 naturally.
The stroke of the gripping mechanism is 90 degrees. A pin located in the motor 27 fixation limits the stroke of the moving pulley 28 for safety reasons. The radius of the pulley is R. The motor shaft 26 extension has a radius r. With the angle measured by the encoder integrated in the motor 27, the opening angle of the user's hand can be calculated. The cable 25 transmission amplifies the motor torque and the encoder resolution by a ratio of R/r.
All the fingers 20, 24 are attached to the gripping mechanism by adjustable straps 30, 31 or other equivalent means.
Additional tactile cues
The lack of tactile information prevents the user to perform common haptic explorations when manipulating virtual or distal objects. For instance, in the case of teleoperated robotic surgery, surgeons cannot palpate the internal tissues to localize hidden anatomical structures. During surgical procedures, palpation is often carried out in order to determine the position of arteries. This task is regularly performed to locate needle insertion sites for regional anesthesia, or to prevent accidental rupture of arteries.
Since user's fingers are constantly in contact with the presented ergonomic handle different tactile cues can be given through it to enhance user's telepresence. In the previous case, to provide surgeons with the sensation of palpating an artery, an array of small pins could provide a pulsating indentation in the finger, see Figure 9(a). This type of tactile display is often actuated pneumatically see reference [8], with dc motors see reference [6] or piezoelectric actuators see reference [1]. The first solution might be preferred because it is a lightweight solution and thus easier to be integrated.
Temperature information can also be displayed directly to the user's fingertip thought a display integrating several Peltier elements 32, see Figure 9(b). Vibration actuators, such as small dc motors with an eccentric mass attached or voice coils, can also convey additional information such as the slippage of an object between the fingertips.
These displays can be integrated on the fixed part of the grasping system under the chosen finger. The control electronics might be preferably apart to reduce the weight and size of the device. In a teleoperation task the information displayed by this system might be measured by sensors integrated in the gripper of the slave robot. For instance, the array of pins 33 could render the information sensed by a matrix of pressure sensors. In the case of thermal information a sensor such as a Resistance Temperature Detector (RTD), a thermocouple or thermistor included in the slave robot sense directly the temperature of the contact point with the object.
If the device is applied in a virtual reality application the device can directly simulate the thermal or tactile characteristics of the virtual object commanded by the computer.
Of course, it is possible to combine different elements that render different tactile cues as described above.
Safety Features: brakes
As it was already mentioned, the ergonomic handle features safety brakes for the orientations. They may comprise a pneumatic brake system (see Figure 10]. The main component of this braking system is a pneumatic hub 40 with a cylindrical air chamber 41 connected to an entrance of air. This cylindrical hub is attached to the fixed link 44 of the DOF by two antirotational pins. A moving shaft 42 passes though the hub 40 without making contact with it and is attached to an external tambour 43.
When the brake is switched off the tambour 43 moves freely around the pneumatic hub 40 concentrically. Therefore, the relative movement between the two links is allowed.
When the brake is activated the air inflates the pneumatic chamber 41 of the hub 40 and thus, it makes contact with the external tambour 43. Consequently, the fix part 44 and the moving shaft 42 are mechanically connected preventing relative movement between them.
Alternatively, magnetic particle brakes or other types of friction brakes can be used to generate a passive resistance or friction in each DOF. In other embodiments, all or some of the actuator and sensor pairs can include only sensors to provide an apparatus without torque or grasping force feedback along designated DOF.
Safety Features: presence sensor
For safety reasons it is also desirable to sense or detect when the user is touching the handle. This measurement will allow the control system to block the user's orientation by enabling the safety brakes when the user's hand releases the handle.
The presence sensor should be able to detect if the handle is being touched, even if the user is wearing rubber gloves or if the hand presents high level of humidity. Additionally, the presence sensor should only detect the user's hand when it is actually in contact with the ergonomic handle and not when it is just near. In this embodiment, the most suitable sensor was found to be a capacitive sensor. Nevertheless, a pressure sensor could be also be used and achieve the same result. Of course, other equivalent means and sensors may be used.
Of course, all the embodiments described above a illustrative examples that should not be construed in a limiting manner. It is possible to use equivalent means and principles within the frame and scope of the present invention.
The device of the present application can be used in many different fields and adapted for said fields (materials, sizes etc): medical applications, simulation applications, game applications, etc. REFERENCES (all incorporated by reference in their entirety in the present application)
1. Hayward, V. & Cruz-Hernandez, M. (2000) Tactile display device using distributed lateral skin stretch. . (Vol: 69, pp:2).
2. Imrhan, S. (1991 ) The Influence of Wrist Position on Different Types of Pinch Strength. Applied Ergonomics . (Vol: 22, pp:379-384).
3. Lawson, E. H., Curet, M. J., Sanchez, B. R., Schuster, R., & Berguer, R. (2007) Postural ergonomics during robotic and laparoscopic gastric bypass surgery: a pilot project. Journal of Robotic Surgery . (Vol: 1 , pp:61 -67).
4. Lee, E., Rafiq, A., Merrell, R., Ackerman, R., & Dennerlein, J. (2005) Ergonomics and human factors in endoscopic surgery: a comparison of manual vs telerobotic simulation systems. Surgical endoscopy . (Vol: 19, pp:1064-1070).
5. Napier, J. R. (1956) The prehensile movements of the human hand. Journal of Bone and Joint Surgery . (Vol: 38, pp:902-913).
6. Ottermo, M. V., Stavdahl, 0., & Johansen, T. A. (2004) Palpation instrument for augmented minimally invasive surgery. . (Vol: , pp:3960-3964).
7. Safwat, B., Su, E. L. M., Gassert, R., Teo, C. L, & Burdet, E. (2009) The Role of Posture, Magnification, and Grip Force on Microscopic Accuracy. Annals of biomedical engineering . (Vol: 37, pp:997-1006).
8. Santos-Carreras, L, Leuenberger, K., Re tornaz, P., Gassert, R., & Bleuler, H. () Design and psychophysical evaluation of a tactile pulse display for teleoperated artery palpation. . (Vol: , pp:5060-5066).
9. Spalter, U. (2006) PhD Thesis. Haptic interface design and control with application to surgery simulation. 10. Yuh-Chuan Shih, Y.-C. O. (2005) Influences of span and wrist posture on peak chuck pinch strength and time needed to reach peak strength. International Journal of Industrial Ergonomics . (Vol: , pp:527-536).

Claims

1. An ergonomic handle comprising:
- a plurality of degrees of freedom of orientation in which at least one of them is accomplished by a double parallelogram;
- a remote center of rotation located inside the user's hand;
- an input sensor per DOF, to measure the user's hand orientation.
2. The handle as claimed in claim 1, comprising a grasping mechanism with an input sensor to measure the user's hand aperture.
3. The handle as claimed in one of the preceding claims, involving all fingers to grasp the device and the thumb to control the action.
4. The handle as defined in one of the preceding claims, in which a moving part of the grasping mechanism has an axis economically located to follow the natural thumb movement.
5. The handle as defined in one of the preceding claims, in which a fixed part of the grasping mechanism has a curved shape to avoid finger tension.
6. The handle as defined in one of the preceding claims, in which the moving part is actuated to provide grasping feedback.
7. The handle as claimed in one of the preceding claims, further comprising brakes to block user's hand orientation.
8. The handle as claimed in one of the preceding claims, further comprising actuators to provide torque feedback.
9. The handle as defined in one of the preceding claims, further comprising in the handle a contact sensor, to detect the presence of the user's hand.
10. The handle as defined in one of the preceding claims, with a safety feature that blocks user's hand movement when the user removes the hand from the handle.
11. The handle as defined in one of the preceding claims, with a safety feature that blocks user's hand movement when a safety issue arises.
12. The handle as claimed in one of the preceding claims, in which the double parallelogram is separated in two parallel link chains to increase the stiffness of the mechanism.
13. The handle as claimed in one of the preceding claims, with split axis to increase the workspace of the mechanism.
14. The handle as defined in one of the preceding claims, to be assembled on another input device providing extra DOF.
15. The handle as defined in one of the preceding claims, comprising Peltier elements to provide temperature tactile sensations.
16. The handle as defined in one of the preceding claims, comprising actuators providing vibrations to recreate tactile sensations on the user's hand skin.
17. The handle as defined in one of the preceding claims, comprising a tactile display composed by an array of pins to display a tactile pattern by indenting the skin of fingertip.
18. The handle as defined in one of the preceding claims, in which the array of pins is actuated in a pulsated manner to simulate heartbeats.
19. A device, such as a haptic device, comprising a handle as defined in one of the preceding claims.
PCT/IB2012/051303 2011-03-18 2012-03-19 Ergonomic handle for haptic devices WO2012127404A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161453972P 2011-03-18 2011-03-18
US61/453,972 2011-03-18

Publications (2)

Publication Number Publication Date
WO2012127404A2 true WO2012127404A2 (en) 2012-09-27
WO2012127404A3 WO2012127404A3 (en) 2012-11-22

Family

ID=45999902

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2012/051303 WO2012127404A2 (en) 2011-03-18 2012-03-19 Ergonomic handle for haptic devices

Country Status (1)

Country Link
WO (1) WO2012127404A2 (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3015081A1 (en) * 2014-10-27 2016-05-04 Karl Storz GmbH & Co. KG Surgical instrument with a manual control device
EP3034028A1 (en) * 2014-12-17 2016-06-22 Suzhou Kang Multi Robot Co Ltd A multi-degree of freedom surgical instrument for minimally invasive surgery
EP3038542A4 (en) * 2013-09-01 2017-02-22 Human Extensions Ltd Control unit for a medical device
CN108472100A (en) * 2016-01-26 2018-08-31 索尼公司 Grip sense feedback device and stylus formula force feeling feedback device
WO2019070734A1 (en) 2017-10-02 2019-04-11 Intuitive Surgical Operations, Inc. End effector force feedback to master controller
WO2019099504A1 (en) 2017-11-15 2019-05-23 Intuitive Surgical Operations, Inc. Master control device with multi-finger grip and methods therefor
EP3463151A4 (en) * 2016-06-03 2020-02-19 Covidien LP Control arm assemblies for robotic surgical systems
EP3658058A4 (en) * 2017-07-27 2021-04-14 Intuitive Surgical Operations, Inc. Medical device handle
WO2021147264A1 (en) * 2020-01-23 2021-07-29 诺创智能医疗科技(杭州)有限公司 Operating assembly and surgical robot
EP3745985A4 (en) * 2018-02-02 2022-03-16 Covidien LP Robotic surgical systems with user engagement monitoring
US11351001B2 (en) 2015-08-17 2022-06-07 Intuitive Surgical Operations, Inc. Ungrounded master control devices and methods of use
US11712314B2 (en) 2017-11-15 2023-08-01 Intuitive Surgical Operations, Inc. Master control device and methods therefor

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7594912B2 (en) 2004-09-30 2009-09-29 Intuitive Surgical, Inc. Offset remote center manipulator for robotic surgery

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6406472B1 (en) * 1993-05-14 2002-06-18 Sri International, Inc. Remote center positioner
US6368332B1 (en) * 1999-03-08 2002-04-09 Septimiu Edmund Salcudean Motion tracking platform for relative motion cancellation for surgery
US7204168B2 (en) * 2004-02-25 2007-04-17 The University Of Manitoba Hand controller and wrist device
US20050252329A1 (en) * 2004-05-13 2005-11-17 Jean-Guy Demers Haptic mechanism

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7594912B2 (en) 2004-09-30 2009-09-29 Intuitive Surgical, Inc. Offset remote center manipulator for robotic surgery

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
HAYWARD, V.; CRUZ-HERNANDEZ, M., TACTILE DISPLAY DEVICE USING DISTRIBUTED LATERAL SKIN STRETCH, vol. 69, 2000, pages 2
IMRHAN, S.: "The Influence of Wrist Position on Different Types of Pinch Strength", APPLIED ERGONOMICS, vol. 22, 1991, pages 379 - 384
LAWSON, E. H.; CURET, M. J.; SANCHEZ, B. R.; SCHUSTER, R.; BERGUER, R.: "Postural ergonomics during robotic and laparoscopic gastric bypass surgery: a pilot project", JOURNAL OF ROBOTIC SURGERY, vol. 1, 2007, pages 61 - 67
LEE, E.; RAFIQ, A.; MERRELL, R.; ACKERMAN, R.; DENNERLEIN, J.: "Ergonomics and human factors in endoscopic surgery: a comparison of manual vs telerobotic simulation systems", SURGICAL ENDOSCOPY, vol. 19, 2005, pages 1064 - 1070, XP019366729
NAPIER, J. R.: "The prehensile movements of the human hand", JOURNAL OF BONE AND JOINT SURGERY, vol. 38, 1956, pages 902 - 913
OTTERMO, M. V.; STAVDAHL, Ø.; JOHANSEN, T. A., PALPATION INSTRUMENT FOR AUGMENTED MINIMALLY INVASIVE SURGERY, 2004, pages 3960 - 3964
SAFWAT, B.; SU, E. L. M.; GASSERT, R.; TEO, C. L.; BURDET, E.: "The Role of Posture, Magnification, and Grip Force on Microscopic Accuracy", ANNALS OF BIOMEDICAL ENGINEERING, vol. 37, 2009, pages 997 - 1006, XP019668359
SANTOS-CARRERAS, L.; LEUENBERGER, K.; RE TORNAZ, P.; GASSERT, R.; BLEULER, H., DESIGN AND PSYCHOPHYSICAL EVALUATION OF A TACTILE PULSE DISPLAY FOR TELEOPERATED ARTERY PALPATION, pages 5060 - 5066
SPALTER, U.: "Haptic interface design and control with application to surgery simulation", PHD THESIS, 2006
YUH-CHUAN SHIH, Y.-C. O.: "Influences of span and wrist posture on peak chuck pinch strength and time needed to reach peak strength", INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS, 2005, pages 527 - 536

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11020197B2 (en) 2013-09-01 2021-06-01 Human Xtensions Ltd. Control unit for a medical device
EP3038542A4 (en) * 2013-09-01 2017-02-22 Human Extensions Ltd Control unit for a medical device
US10149730B2 (en) 2013-09-01 2018-12-11 Human Extensions Ltd. Control unit for a medical device
US10105127B2 (en) 2014-10-27 2018-10-23 Karl Storz Se & Co. Kg Surgical instrument with a manual control
EP3015081A1 (en) * 2014-10-27 2016-05-04 Karl Storz GmbH & Co. KG Surgical instrument with a manual control device
EP3034028A1 (en) * 2014-12-17 2016-06-22 Suzhou Kang Multi Robot Co Ltd A multi-degree of freedom surgical instrument for minimally invasive surgery
US11351001B2 (en) 2015-08-17 2022-06-07 Intuitive Surgical Operations, Inc. Ungrounded master control devices and methods of use
CN108472100A (en) * 2016-01-26 2018-08-31 索尼公司 Grip sense feedback device and stylus formula force feeling feedback device
EP3409232A4 (en) * 2016-01-26 2018-12-05 Sony Corporation Grip force sensation feedback device and stylus-type force sensation feedback device
US11058504B2 (en) 2016-06-03 2021-07-13 Covidien Lp Control arm assemblies for robotic surgical systems
US11653991B2 (en) 2016-06-03 2023-05-23 Covidien Lp Control arm assemblies for robotic surgical systems
EP3463151A4 (en) * 2016-06-03 2020-02-19 Covidien LP Control arm assemblies for robotic surgical systems
US11672621B2 (en) 2017-07-27 2023-06-13 Intuitive Surgical Operations, Inc. Light displays in a medical device
US11751966B2 (en) 2017-07-27 2023-09-12 Intuitive Surgical Operations, Inc. Medical device handle
EP3658058A4 (en) * 2017-07-27 2021-04-14 Intuitive Surgical Operations, Inc. Medical device handle
EP3691555A4 (en) * 2017-10-02 2021-07-14 Intuitive Surgical Operations, Inc. End effector force feedback to master controller
WO2019070734A1 (en) 2017-10-02 2019-04-11 Intuitive Surgical Operations, Inc. End effector force feedback to master controller
US11666402B2 (en) 2017-10-02 2023-06-06 Intuitive Surgical Operations, Inc. End effector force feedback to master controller
EP3709923A4 (en) * 2017-11-15 2021-08-11 Intuitive Surgical Operations, Inc. Master control device with multi-finger grip and methods therefor
WO2019099504A1 (en) 2017-11-15 2019-05-23 Intuitive Surgical Operations, Inc. Master control device with multi-finger grip and methods therefor
US11712314B2 (en) 2017-11-15 2023-08-01 Intuitive Surgical Operations, Inc. Master control device and methods therefor
US20200275985A1 (en) * 2017-11-15 2020-09-03 Intuitive Surgical Operations, Inc. Master control device with multi-finger grip and methods therefor
EP3745985A4 (en) * 2018-02-02 2022-03-16 Covidien LP Robotic surgical systems with user engagement monitoring
WO2021147264A1 (en) * 2020-01-23 2021-07-29 诺创智能医疗科技(杭州)有限公司 Operating assembly and surgical robot

Also Published As

Publication number Publication date
WO2012127404A3 (en) 2012-11-22

Similar Documents

Publication Publication Date Title
WO2012127404A2 (en) Ergonomic handle for haptic devices
US6413229B1 (en) Force-feedback interface device for the hand
US20060106369A1 (en) Haptic interface for force reflection in manipulation tasks
Hong et al. Design of a novel 4-DOF wrist-type surgical instrument with enhanced rigidity and dexterity
EP0981423B1 (en) Force-feedback interface device for the hand
EP2919948B1 (en) Hand controller device
JP5916320B2 (en) Remote control device
AU2018273807B2 (en) Electromechanical robotic manipulandum device
Hagn et al. Telemanipulator for remote minimally invasive surgery
Kim et al. S-surge: Novel portable surgical robot with multiaxis force-sensing capability for minimally invasive surgery
Park et al. A dual-cable hand exoskeleton system for virtual reality
O’malley et al. Haptic interfaces
Fong et al. EMU: A transparent 3D robotic manipulandum for upper-limb rehabilitation
Naidu et al. A 7 DOF exoskeleton arm: Shoulder, elbow, wrist and hand mechanism for assistance to upper limb disabled individuals
JP2002182817A (en) Inner force representing device
Low et al. A review of master–slave robotic systems for surgery
Secco et al. A wearable exoskeleton for hand kinesthetic feedback in virtual reality
US11504200B2 (en) Wearable user interface device
Li et al. Design and performance characterization of a soft robot hand with fingertip haptic feedback for teleoperation
Park et al. Development of a dual-cable hand exoskeleton system for virtual reality
Sanchez et al. Foot control of a surgical laparoscopic gripper via 5dof haptic robotic platform: Design, dynamics and haptic shared control
Mozaffari Foumashi et al. State-of-the-art of hand exoskeleton systems
Kim et al. S-surge: A portable surgical robot based on a novel mechanism with force-sensing capability for robotic surgery
Sun et al. Design of a bidirectional force feedback dataglove based on pneumatic artificial muscles
Mustafa et al. Optimal design of a bio-inspired anthropocentric shoulder rehabilitator

Legal Events

Date Code Title Description
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12716618

Country of ref document: EP

Kind code of ref document: A2